During the treatment of human or animal tissue, in particular during minimally invasive operations or even during therapies, instruments are often introduced into the body and have to be moved at a site of application. Additionally, it is often necessary to perform mechanical work at the site of application. Typical examples of this are the devitalisation and/or removal of tumour tissue. Another typical example is the treatment of a cholecystolithiasis (gall-bladder stone) or the removal of nephroliths from kidney tracts or urinary tracts. In many cases, working with an endoscope is problematical because the movement of the actual instrument seated at the distal end of the endoscope presents problems.
Accordingly, a device that facilitates the movement of an instrument within a body or an area of tissue without a mechanical connection to the exterior is desired.